1. Field of the Invention
The invention relates to a touch panel. Particularly, the invention relates to a resistive touch panel.
2. Description of Related Art
With quick development of technology, to achieve features of easy carry, small size, and intuitive and user-friendly operation, input devices of many information products (for example, mobile phones, tablet PCs, and computer screens, etc) have changed from conventional keyboards and mouses to touch panels. The touch panel can also be referred to as a touch screen or a soft-touch screen, etc.
Divided by detection techniques of touch points, the touch panels include resistive, capacitive, acoustic sensing, infrared sensing, electromagnetic induction touch panels, etc. FIG. 1 is a schematic diagram illustrating a touch principle of a resistive touch panel 100. As shown in FIG. 1, the resistive touch panel 100 is composed of two even resistive conductive layers 110 and 120. The resistive conductive layers 110 and 120 can be indium tin oxide layers formed by indium tin oxide (ITO). Soft spacers 130 are disposed between the two resistive conductive layers 110 and 120 for spacing the resistive conductive layers 110 and 120 to avoid mutual contact there between.
In this way, under a pressure of user's finger 150 or a penpoint, the soft resistive conductive layer 110 contacts the conductive layer 120 as that shown by dot lines of FIG. 1, and the touch panel 100 obtains a corresponding touch point, so that the information product can execute a corresponding operation. Therefore, the touch panel 100 can replace a mechanical button panel and present a vivid image effect through a liquid crystal screen.
Limited by an operation principle of the conventional resistive touch panel (for example, a conductive layer structure of a 4-wire or a 5-wire resistive touch panel, and a touch point detecting method thereof), only coordinates of a single touch point can be detected when the user touches the touch panel. When there are more than two touch points, correct coordinate values of the touch points cannot be detected, not to mention to detect whether the touch point slides. Therefore, the conventional resistive touch panel is hard to implement a multi-touch function and detection for touch point sliding.